Axions and other (Super-)WISPs

We present some bottom-up motivations of axions and other weakly interacting sub-eV particles (WISPs) coupling to photons. Typically, these light particles are strongly constrained by their production or interaction in astrophysical and cosmological environments. Dedicated laboratory searches can provide complementary probes that are mostly less sensitive but also less model-dependent. We briefly comment on future experiments with the potential to discover photon oscillation effects in kinetic mixing scenarios with massive hidden photons.